Technical Field
This application relates generally to systems and methods used to remove contaminants from oilfield effluents, and more particularly, to systems and methods used to remove hydrogen sulfide from oilfield effluents.
Background Information
Oilfield effluents, including crude oil, produced water and flowback fracturing water, often contain dissolved hydrogen sulfide. Hydrogen sulfide is highly corrosive and may damage equipment used in oil and gas refining processes. Hydrogen sulfide is also toxic to humans and presents a significant health risk to workers in the oil and gas refining industry. Various transportation rules and guidelines may require that hydrogen sulfide concentrations not exceed certain levels.
Known methods used to remove hydrogen sulfide from oilfield effluents often include adding large amounts of scavenger chemicals or utilizing a stripping gas. These methods are often expensive, complex, time-consuming, unable to be easily transported to and from a site, and ineffective at removing large-scale quantities of hydrogen sulfide from the oilfield effluents. Moreover, utilizing a stripping gas may also remove low boiling point hydrocarbons, such as propane, isobutene, n-butane, isopentane, n-pentane, hexane and the like, which are desirable to retain in oilfield effluents such as crude oil. Thus, there is a continued need in the industry for systems and methods to remove hydrogen sulfide from oilfield effluents that are cheaper, simpler, faster, easily set-up and transported to and from a site, and more effective at removing large-scale quantities of hydrogen sulfide from oilfield effluents.